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Here is How to Stay Hydrated When Hiking

    How much water should you bring on a hike?

    Just like shoe sizes or Starbucks orders, no single answer can cover all the bases when it comes to staying hydrated when hiking. For instance, each person reacts to physical duress, activity and heat in different ways. There are a ton of factors to be considered such as BMI, physical shape, sun exposure, distance, diet, and so much more.

    Water in your gut keeps you off your butt!

    Chris McEvoy
    girl walking on trail in silverton colorado

    More is always better when it comes to hydration prep. Everyone has that friend who gives you sh– about carrying too much water weight. Just remember, you can only lead a horse to water, but not force them to drink. Darwin has a way of dealing with these sorts.

    How does the lack of water affect your body?

    • .5% water loss – Increased strain on the heart
    • 1% water loss – Reduced aerobic endurance
    • 3% water loss – Reduced muscular endurance
    • 4% water loss – Reduced muscle strength, fine motor skills, and heat cramps
    • 5% water loss – Heat exhaustion, cramping, fatigue, and reduced mental capacity
    • 6% water loss – Physical exhaustion, heatstroke, and coma

    You can lose up to 60 ounces of water per hour when hiking in 90° heat. That’s about 4% of the body weight of a 150 lb male.

    Emma Greguska, ASU
    girk with dog hiking in desert in arizona

    Drinking Water makes you smarter!

    Your brain is about 75% water. As a result of being dehydrated, it shrinks. Studies have been done to see the effect of water and cognitive abilities showing that there is a direct correlation between hydration and making sure your noodle is operating at 100%.

    You’re not thinking, If you’re not drinking.

    Gray Jolly, Old Hickory Council

    Stay hydrated when hiking. Like, for real.

    Don’t put yourself, your health or others at risk for something as simple and common sense as maintaining proper hydration in the backcountry. You have so many other things to concentrate on, such as taking in the epic views, setting up killer instagram-worthy camp sites and not becoming bear food. Drink plenty of water and urge others to follow your lead.

    Hydration Calculator

    The best way to get an idea about how much water YOU should bring with you is by paying attention to your personal hydration loss. Use this method to get a baseline for the amount of water you should be bringing with you.

    1. Weigh yourself before you go on a hike – Drop the boots, backpack, hiking poles, camera, and sunscreen. Get down to your skivvies and hit the scale. (example: 160 lbs)
    2. Take a note of how much water you bring – To make this super easy, fill up your Nalgene or bladder all the way. We will subtract the amount when you’re all done so we know exactly(ish) how much water you consumed. (example: 2L of water)
    3. Take a hike – wherever, however long. It’s your world, man.
    4. Weigh yourself again – Hit the scale again and take note of your weight. (skivvies only again!) (example: 158lbs)
    5. Calculate weight loss – Subtract your After weight from your Before weight to see how much was lost. (example: 160lbs – 158lbs = 2lbs)
    6. Get out the calculator – Multiply your starting weight by 0.01. (example: 160lbs x 0.01 = 1.6lbs)
    7. Now, what does that number mean? I NEED TO BRING MORE WATER. You want those 2 numbers to be the same, OR you want the final number to be greater – which means you are properly hydrated.
      • Let’s break it down:
      • On this hike, I drank my entire water supply of 2L and was dripping sweat. Granted, I live in Phoenix and it was 108° outside with no shade. For my numbers, my weight loss was 2 lbs, and 1% of my starting body weight was 1.6 lbs.
      • 2lbs > 1.6lbs. As a result, I know that I need to bring more water in order to stay 100% hydrated. Ideally, about 2.5L on a hot day like that.

    By doing a couple of these tests, I now have an insanely accurate idea about how much water I need to realistically stay hydrated when hiking, but just know, that fluid needs change with seasons, temps, elevation and how much of a banger you went on last night at the pub.

    EXTRA CREDIT : Here’s a test that can be done at home:

    • Empty your bladder (pee!)
    • Chug about 3 cups of water
    • Measure how much you pee an hour later (take a guess-timate!)
    • If you peed less than 1 cup, you were dehydrated

    The point of that super fun exercise to take notice of how you felt before and after the experiment. Did you feel dehydrated? Brain fog? fatigue? Did it clear up? Were you able to notice that you actually were in need of some water? It could be surprising to most of us that we are actually in a constant state of dehydration without ever knowing it.

    Hiking Hydration Hack

    If using a hydration bladder: Fill 2/3 of the way with water and then pack ice in there. Why? Because cold water gets sucked in about 20% faster (source: How Not to Die, a book by Michael Greger MD., FACLM)

    If using water bottles: Fill one full of water. Fill the other with a mix of water and ice. Drink the one without ice first. This way you have nice crisp, cold water to look forward towards the end of your hike.

    Our Favorite Hydration Products

    3 of our favorites: For the hydration bladder peeps out there, check out some of Gregory Mountain Products hiking packs. We love these because they have the mesh panel backing to kick down on the sweat game, gorgeous popping colorways and are built to last. For our water bottle lovers, check out what GRAYL has been cooking up with their 16.9oz Ultrapress – just may save your life one day. And for a solid staple, reducing the use of plastic throwaways, a simple Nalgene.

    Keep it Clean

    For those of you who like the Nalgene. Don’t forget proper maintenance! Wash your bottle after every use and every couple months do a deep clean with baking soda. How to Below:

    Want to remember this for later? PIN THESE TO YOUR FAVORITE BOARD!

    An Easy Guide To Cleaning Your Water Bottle